Method for synthesizing multilayer graphene

Abstract

A method for synthesizing a multilayer graphene is provided. Specifically, the multilayer graphene can be produced by performing a step of forming a catalytic metal layer on a substrate, a step of heat-treating the catalytic metal layer on the substrate while supplying methane gas, and a step of synthesizing a multilayer graphene on the heat-treated catalytic metal layer. As described above, the multilayer graphene having a large area can be grown directly on a substrate, by heat-treating the catalytic metal layer using methane gas, prior to the step of synthesis of graphene. In addition, as the the number of layer of the multilayer graphene can be controlled by changing the synthesis time of the multilayer graphene, the multilayer graphene with the desired number of layers can be easily produced.

What is claimed is: 
     
       1. A method for synthesizing a multilayer graphene, comprising:
 forming a catalytic metal layer on a substrate; 
 forming a pattern of asperities on a surface of the catalytic metal layer by subjecting the catalytic metal layer to a heat treatment by supplying methane gas,
 wherein the pattern of asperities formed on the surface of the catalytic metal layer acts as a seed capable of growing the multilayer graphene; and 
 
 depositing the multilayer graphene onto the surface of the catalytic metal layer having the pattern of asperities, comprising heat treating the catalytic metal layer in a gas comprising a carbon source, hydrogen and argon for a time according to a number of layer of the multilayer graphene to be formed. 
 
     
     
       2. The method for synthesizing a multilayer graphene according to  claim 1 , wherein the catalytic metal layer includes one or more selected from the group consisting of copper (Cu), nickel (Ni), iron (Fe), platinum (Pt), aluminum (Al), cobalt (Co), ruthenium (Ru), palladium (Pd), chromium (Cr), magnesium (Mg), manganese (Mn), gold (Au), silver (Ag), molybdenum (Mo), rhodium (Rh), tantalum (Ta), titanium (Ti), tungsten (W), uranium (U), vanadium (V), zirconium (Zr), and iridium (Ir), brass, bronze, and stainless steel. 
     
     
       3. The method for synthesizing a multilayer graphene according to  claim 1 , wherein the step of forming a catalytic metal layer on a substrate is performed using one or more methods selected from the group consisting of an electron-beam evaporation deposition method, a thermal evaporation deposition method, a laser molecular beam epitaxy (L-MBE), a pulsed laser deposition (PLD), an electro-plating method and a sputtering method. 
     
     
       4. The method for synthesizing a multilayer graphene according to  claim 1 , wherein subjecting the catalytic metal layer to the heat treatment comprises heating the substrate at a temperature ranging from 800° C. to 1100° C. for 10 to 120 minutes. 
     
     
       5. The method for synthesizing a multilayer graphene according to  claim 1 , wherein depositing the multilayer graphene onto the surface of the catalytic metal layer comprises:
 supplying a reaction gas comprising a carbon source onto the surface having the pattern of asperities of the catalytic metal layer to form the multilayer graphene; 
 causing the deposition of the multilayer graphene on the surface of the catalytic metal at a temperature ranging from a room temperature to 1200° C.; and 
 cooling the multilayer graphene. 
 
     
     
       6. The method for synthesizing a multilayer graphene according to  claim 5 , wherein the carbon source includes one or more materials selected from the group consisting of a natural graphite, a synthetic graphite, a highly ordered pyrolytic graphite (HOPG), an activated carbon, a carbon monoxide, a carbon dioxide, a methane, an ethane, an ethylene, a methanol, an ethanol, an acetylene, a propane, a propylene, a butane, a butadiene, a pentane, a pentene, a cyclopentadiene, a hexane, a cyclohexane, a benzene, a toluene, a polymethyl methacrylate (PMMA), a polystyrene, a polyacrylonitrile (PAN), and PEDOT:PSS. 
     
     
       7. The method for synthesizing a multilayer graphene according to  claim 1 , wherein, in the stage of synthesizing the multilayer graphene, the number of layer of the multilayer graphene is controlled by changing the synthesis time of the multilayer graphene. 
     
     
       8. The method for synthesizing a multilayer graphene according to  claim 1 ,
 wherein depositing the multilayer graphene onto the surface of the catalytic metal layer comprises performing deposition of the multilayer graphene for a time ranging from 10 minutes to 20 minutes, and 
 wherein the multilayer graphene is a bilayer graphene. 
 
     
     
       9. The method according to  claim 1 , wherein forming the catalytic metal layer on the substrate comprises forming the catalytic metal layer directly on a substrate of an electronic device. 
     
     
       10. The method according to  claim 1 , wherein the catalytic metal layer comprises at least one metal selected from the group consisting of aluminum (Al), ruthenium (Ru), palladium (Pd), chromium (Cr), magnesium (Mg), manganese (Mn), silver (Ag), molybdenum (Mo), rhodium (Rh), tantalum (Ta), titanium (Ti), tungsten (W), uranium (U), vanadium (V), zirconium (Zr), and iridium (Ir).